• Journal of electromagnetic engineering and science
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• v.6 no.1
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• pp.47-52
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• 2006

The objective of this study is to evaluate the effects of size and permittivity on the specific absorption rate(SAR) values of rat brains during microwave exposure at mobile phone frequency bands. A finite difference time domain (FDTD) technique with perfect matching layer(PML) absorbing boundaries is used for this evaluation process. A color coded digital image of the Sprague Dawley(SD) rat based on magnetic resonance imaging(MRI) is used in FDTD calculation with appropriate permittivity values corresponding to different tissues for 3, 4, 7, and 10 week old rats. This study is comprised of three major parts. First, the rat model structure is scaled uniformly, i.e., the rat size is increased without change in permittivity. The simulated SAR values are compared with other experimental and numerical results. Second, the effect of permittivity on SAR values is examined by simulating the microwave exposure on rat brains with various permittivity values for a fixed rat size. Finally, the SAR distributions in depth, and the brain-averaged SAR and brain 1 voxel peak SAR values are computed during the microwave exposure on a rat model structure when both size and permittivity have varied corresponding to different ages ranging from 3 to 10 weeks. At 900 MHz, the simulation results show that the brain-averaged SAR values decreased by about 54 % for size variation from the 3 week to the 10 week-old rat model, while the SAR values decreased only by about 16 % for permittivity variation. It is found that the brain averaged SAR values decreased by about 63 % when the variations in size and permittivity are taken together. At 1,800 MHz, the brain-averaged SAR value is decreased by 200 % for size variation, 9.7 % for permittivity variation, and 207 % for both size and permittivity variations.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.674-679
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• 2002

The toxicity and bioaccumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) continues to be a focus of research in human and various species. The main human exposure is via the dietary route. This study was carried out to investigate the protective effect of Cornu Cervi Parvum extract on clinical parameters and hepatotoxicity in Sprague-Dawley rat (SD rat) accutely exposured to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Male SD rats received single intraperitoneal (ip) injection of TCDD (40 ㎍/kg), and administered 10 or 20 mg/kg/day of the ethanol extract oral injection for 4 weeks from 1 week before TCDD treatment. The gain in body weight was less in group treated with TCDD than in CON group, while that of C/H+ TCDD group (Cornu Cervi Parvum extract 20 mg/kg/day) increased. The decrease in spleen and testis weight caused by TCDD was prevented by Cornu Cervi Parvum extract 20 mg/kg/day. The fluctuation in BUN content, WBC and platelet count by TCDD intoxication were significantly attenuated by the ethanol extract treatment (20 mg/kg/day for 4 weeks). Treatments of rats with the extract (10 or 20 mg/kg/day) were significantly reduced AST and ALT levels compared with TCDD-treated group. Moderate swelling of hepatocytes, hyperchromatism, acidophilic cytoplasm and cytoplasmic vacuolation were observed in TCDD-treated animals (TCDD group). The administration of EtOH extract 10 or 20 mg/kg along with TCDD significantly alleviated the liver histopathological alteration induced by TCDD. These results suggest that Cornu Cervi Parvum extract can be useful as a protective agent against TCDD, an endocrine disruptor.

• Applied Microscopy
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• v.32 no.3
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• pp.285-290
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• 2002

The therapeutic effect of safflower seed powder on experimental osteoporosis in the rat induced by ovariectomy was evaluated. Thirty Sprague-Dawley rats were ovariectomized at the age of 12 weeks. Seven weeks postovariectomy, rats were divided into two groups: control and safflower seed powder treated group. Five animals from each group were sacrificed at the following time points: 1, 3, and 5 weeks. Scanning electron microscopic observation and morphometric analysis of the tibiae epiphysis showed that the administration of safflower seed powder significantly prevented reduction of cortical bone width and bone volume compared with the control group. In conclusion, safflower seed powder contains something that prevent bone loss due to estrogen deficiency, and was effective in preventing the osteoporotic decrease of bone mass.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.892-895
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• 2005

This study investigated changes of mechanical characteristics in the trabecular and cortical bone of the lumbar vertebrae of the ovariectomised(OVX) rat. In previous researches, there were many studies for morphology of osteoporotic bones based on Micro-CT (Micro - Computed Tomography). However, there were few studies for detecting and tracking changes of mechanical characteristics in the trabecular bone and cortical bone of the lumbar vertebrae for the OVX rat. For this study, one female Sprague-Dawley rat was used: an OVX rat. The 4th lumbar of the OVX rat was utilized as a specimen. Detecting and tracking changes of mechanical characteristics could be investigated in the trabecular and cortical bone of the lumbar vertebrae for an OVX rat using In-vivo Micro-CT. An OVX rat was scanned at week 0 (just before surgery), at week 4, and week 8 after surgery. Micro finite element(${\mu}\;FE$) analysis was used to investigate mechanical characteristics in the trabecular and cortical bone of the lumbar vertebrae for an OVX rat.

• Journal of Environmental Science International
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• v.12 no.10
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• pp.1131-1136
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• 2003

To examine whether salt stress would alter or not contractility of isolated rat aorta, under anesthesia with sodium pentobarbital(50 mg kg-1 i.p.), male Sprague Dawley rats(300-330 g) were subjected to 0, 50, and 150 mM of sodium chloride at 37$^{\circ}C$ for 60 min. where as the sham group was left at modified Krebs-bicarbonate solution. To measure contractile response of vascular ring preparation isolated from rat was determined in organ bath and was recorded on physiograph connected to isometric transducer. And the strip was checked for expression of heat shock protein(Hsp) by Western blotting. One, three and eight hours later, we measured vascular contractility of isolated rat aorta treated with KCI, phenylephrine from organ bath study. The dose-vascular responses of potassium chloride and phenylephrine showed a little augmentation by NaCl concentration in the strips exposed to NaCl for 8 hours. And the response of relaxation induced by nitroprusside and acetylcholine was not influenced by NaCl stress in isolated aorta ring for 8 hours, respectively. Expression pattern of Hsp 70 of vascular muscle in isolated rat aorta showed a little increase in 150 mM NaCl group at 8 hours after NaCl treatment but not at 3 hours, and Hsp 60 expression of rat aorta was markedly increased in 50 mM NaCl group at 8 hours after NaCl treatment. Taken together, NaCl induced dose-and time dependent accumulation of the Hsp but not affected contraction of rat aorta. These data suggest that short term high salt stress was not sufficient to induce hypertension of rat aorta.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.236-239
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• 2005

This study investigated the effect of ovariectomy (OVX) on the rat bone fur long term (22 weeks). In previous researches, there were many studies for morphology of OVX-induced osteoporotic bones based on micro-Computed Tomography (micro-CT). However, there were few studies fpr detecting and tracking changes of mechanical characteristics in the lumbar vertebrae of OVX rat fur long-term. For this study, one female Sprague-Dawley rat was used: an OVX rat. The 4th lumbar of the OVX rat was utilized as a specimen. Morphological characteristics could be investigated fur the lumbar vertebrae in an OVX rat by using in-vivo Micro-CT. An OVX rat was scanned at week 0 (just before surgery), at week 4, at week 8, at week 16 and at week 22 after surgery. Micro finite element $({\mu}FE)$ analysis was used to investigate mechanical characteristics in the lumbar vertebrae for an OVX rat.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.53-57
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• 1996

As the production of chonma became increased by the farmer's cultivation, developments of the processed food such as tea using chonma have been actively pursued. In the present study, the components of chonma and its beneficial effects on health using SD (Sprague-Dawley) rat model were analyzed. The contents of moisture, protein, ash, fat and fiber in dried-chonma were 11.8, 7.6, 3.2, 0.5, and 3.9%(w/w), respectively. The contents of calcium, sodium, iron, phosphorus, magnesium and potassium were 121, 83, 6.2, 170, 69 and 1,278 mg%. When chow diets containing 0, 0.15, 1.5 or 5.0% chonma powder were fed to SD rats for 4 weeks, no significant differences were observed in the composition of the large-intestinal flora, ${\beta}-glucuronidase$ level of the large-intestinal contents and the weight gains of rats. The level of ${\beta}-glucosidase$ was higher and the serum cholesterol level was lower in 5.0% chonma group compared with control group. The highest sedative effect was shown in 0.15% chonma group.

• Journal of Acupuncture Research
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• v.32 no.4
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• pp.77-89
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• 2015

Objectives : To evaluate the safety of multiple-dose intramuscular Shinbaro Pharmacopuncture in male and female Sprague-Dawley(SD) rats over a period of 4 weeks(12 sessions). Methods : In order to test the safety of multiple-dose intramuscular Shinbaro Pharmacopuncture we used 40 healthy male and female 6-week old SD rats(male weight 171.79~196.37 g, female weight 127.93~146.43 g). Shinbaro Pharmacopuncture was administered intramuscularly to male and female SD rats at doses of 4.6 (low dose group, n=10), 9.2 (moderate dose group, n=10), and 18.5 mg/kg(high dose group, n=10), respectively. General symptoms, body weight changes, blood tests, biochemical testing, necropsy, organ weight and histopathogical findings were examined over a 4-week period. Results : 1. No mortalities or adverse effects were caused by the investigational substance were observed during the study period. 2. There was no significant difference in body weight caused by the the investigational substance across all groups. 3. No significant between-group difference was found to be caused by the investigational substance in blood tests and biochemical testing. 4. No abnormalities were detected by a necropsy examination with the unaided eye at the macro level after treatment with the investigational substance. 5. Difference in organ weight between groups caused by the investigational substance was not found. 6. All groups did not exhibit pathological findings caused by the investigational substance in histopathogical examination. Conclusions : According to these results, Shinbaro Pharmacopuncture has no systemic or organ toxicity with multiple-dose intramuscular administrations in male and female SD rats over a 4-week period (12 sessions). These results imply that no adverse effects are observed at a level (NOAEL) of Shinbaro Pharmacopuncture of 18.5 mg/kg.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.3
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• pp.111-123
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• 2008

Objectives : We aimed to investigate therapeutic effect of Bojungikgitang-gamibang(BI) and Mahwangshingungsan(MS) by observing changes in blood cells and the nasal mucosa of Sprague-Dawley(SD) rats with allergic rhinitis. Methods : Twenty-four SD rats were divided into three groups: normal, control, and sample group. Allergic rhinitis was induced in the control and sample group by intraperitoneal and intranasal sensitization with 0.1% and 0.4% Ovalbumin solution. Then BI was orally administered only to the sample group along with MS for 28days, while the rats in the control group was given normal saline. Results : BI and MS showed significantly decreased IgE level on the serum of the rat model, Bl and MS showed significantly decreased eosinophil level on the blood of the rat model. BI and MS inhibited the inflammatory reaction on the nasal mucosal tissue, according to nasal mucosal biopsy. Bl and MS had anti-allergic according to level, eosinophil level, nasal mucosal biopsy. BI and MS had no hepatoxicity, according to AST and ALT on the serum. Conclusion : According to the above results, it is considered that Bl and MS is helpful in treatment of allergic rhinitis.

• Biomolecules & Therapeutics
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• v.18 no.2
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• pp.166-170
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• 2010

Recently some researches have established that the melatonin, secreted by pineal gland, may evoke the changes of contractile responses on smooth muscles. We examined the effects of melatonin on the motility of rat pyloric antrum and which mechanism might be involved in the effects. Pyloric antral strips from the stomach of 20 Sprague-Dawley rats were prepared for isometric tension recording in organ bath. The strips were precontracted by acetylcholine and high-KCl solutions. In precontracted conditions the tensions were increased by accumulative application of melatonin ($10^{-8}-10^{-4}$ M) dose-dependently, even in resting states. And the effects were almost disappeared when the concentrations of ACh were over than 10 ${\mu}M$. The effects of melatonin were inhibited by pretreatment of 10 mM TEA and/or 10 ${\mu}M$ 4-AP and rarely affected by pretreatment of 1 mM TEA, 10 ${\mu}M$ glibenclamide and 10 ${\mu}M$ verapamil respectively. From these results it is concluded that the contractile responses of smooth muscles of rat pyloric antrum were enhanced by melatonin application and the mechanism might be concerned with the inhibition of some voltage-dependent potassium channels.